Folded aneurysm treatment device and delivery method

ABSTRACT

Devices can generally include an implant having a braided section that can be implanted in a deployed state such that, in the deployed state, the braided section folds to form an outer occlusive sack extending across a neck of an aneurysm to engage a wall of the aneurysm from within a sac of the aneurysm and an inner occlusive sack forming a trough nested within the outer occlusive sack. The implant can be closed at one or more of the braid ends to define a substantially enclosed bowl-shaped volume.

FIELD OF THE INVENTION

The present invention generally relates to medical instruments, and moreparticularly, to implants for aneurysm therapy.

BACKGROUND

Cranial aneurysms can be complicated and difficult to treat due to theirproximity to critical brain tissues. Prior solutions have includedendovascular treatment whereby an internal volume of the aneurysm sac isremoved or excluded from arterial blood pressure and flow. Suchsolutions, however can result in the interior walls of the aneurysmbeing subjected to flow of blood and related blood pressure even aftertreatment, and the aneurysm can rupture as a result.

Current alternatives to endovascular or other surgical approaches caninclude occlusion devices that either fill the sac of the aneurysm withembolic material or treating the entrance or neck of the aneurysm. Bothapproaches attempt to prevent blood flow into the aneurysm. When fillingan aneurysm sac, the embolic material clots the blood, creating athrombotic mass within the aneurysm. When treating the aneurysm neck,blood flow into the entrance of the aneurysm is inhibited, inducingvenous stasis in the aneurysm and facilitating a natural formation of athrombotic mass within the aneurysm.

Current occlusion devices typically utilize multiple embolic coils toeither fill the sac or treat the entrance. In either treatment,obtaining an embolic coil packing density sufficient to either occludethe aneurysm neck or fill the aneurysm sac is difficult and timeconsuming. Further, aneurysm morphology (e.g. wide neck, bifurcation,etc.) can required ancillary devices such a stents or balloons tosupport the coil mass and obtain the desired packing density.

Naturally formed thrombotic masses formed by treating the entrance ofthe aneurysm with embolic coils can improve healing compared to aneurysmmasses packed with embolic coils by reducing possible distention fromarterial walls and permitting reintegration into the original parentvessel shape along the neck plane. However, embolic coils delivered tothe neck of the aneurysm can potentially have the adverse effect ofimpeding the flow of blood in the adjoining blood vessel; at the sametime, if the entrance is insufficiently packed, blood flow can persistinto the aneurysm. Properly implanting embolic coils is thereforechallenging, and once implanted, the coils cannot easily be retracted orrepositioned.

Furthermore, embolic coils do not always effectively treat aneurysms asaneurysms treated with multiple coils often reanalyze or compact becauseof poor coiling, lack of coverage across the aneurysm neck, because offlow, or even aneurysm size.

An example alternative occlusion device is described in U.S. Pat. No.8,998,947. However, this approach relies upon the use of embolic coilsor mimics the coil approach and therefore suffers many of thelimitations of embolic coil approaches such as difficulty achieving asafe packing density and inability to reposition once implanted.

It is therefore desirable to have a device which easily, accurately, andsafely occludes a neck of an aneurysm or other arterio-venousmalformation in a parent vessel without blocking flow into perforatorvessels communicating with the parent vessel.

SUMMARY

Disclosed herein are various exemplary devices for occluding an aneurysmthat can address the above needs. The devices can generally include animplant having a braided section that can be implanted in a deployedstate such that, in the deployed state, the braided section folds toform an outer occlusive sack extending across a neck of an aneurysm toengage a wall of the aneurysm from within a sac of the aneurysm and aninner occlusive sack forming a trough nested within the outer occlusivesack. The implant can be closed at one or more of the braid ends todefine a substantially enclosed bowl-shaped volume.

An example device for occluding an aneurysm can include an implant thatis movable from a collapsed state to a deployed state. The implant canhave a proximal end, a distal end, and a braided segment forming asubstantially continuous braided structure between the proximal end andthe distal end. In the deployed state, the implant can have an outerocclusive sack, an inner occlusive sack, and a fold between the outerocclusive sack and the inner occlusive sack. The outer occlusive sackcan extend from the proximal end of the implant and can occlude ananeurysm neck. The inner occlusive sack can extend from the distal endof the implant and form a trough within the outer occlusive sack.

The braided segment can have a first portion that is capable ofself-expanding to form the outer occlusive sack and a second portionthat is capable of self-inverting to form the inner occlusive sack.

In the deployed state, the outer occlusive sack can extend to ananeurysm wall to provide a force against the aneurysm wall. In thedeployed state, opposition of the outer occlusive sack to the aneurysmwall can be sufficient to maintain the position of the implant withinthe aneurysm.

The device can further include an embolic filler that is implantable ina sac of the aneurysm. In the deployed state, the implant can inhibitthe embolic filler from exiting the sac, and the embolic filler canprovide a force to appose the implant to the aneurysm wall.

In the collapsed state, the implant can be sized to be delivered to theaneurysm through a microcatheter.

Either the proximal end or the distal end, or both, can be closed. Thedevice can include end closure mechanisms positioned at one or bothends. The end closure mechanisms can be bands or end caps.

The braided segment can be made of a memory shape material having afirst, predetermined shape and a second, deformed shape. The braidedsegment can be in the second, deformed shape when the implant is in thecollapsed state and can move to a third, deployed shape when the implantis in the deployed state. The third, deployed shape can be based atleast in part on the predetermined shape and the shape of the aneurysmwall.

In the deployed state, the outer occlusive sack can seal the aneurysmneck to deflect, divert, and/or slow a flow of blood into the aneurysm.In the deployed state, the implant can define a substantially enclosedvolume. In the deployed state, the distal end and the proximal end ofthe implant can each be positioned along an axis approximatelyperpendicular to the aneurysm neck and approximate a center of theaneurysm neck.

The implant can be implantable in an aneurysm positioned adjacentbifurcated blood vessel branches, and the implant can be delivered tothe aneurysm through a stem branch feeding the bifurcated blood vesselbranches.

In another example, an implant for treating an aneurysm can have abraided mesh that is movable to an implanted configuration such that thebraided mesh has a substantially contiguous surface defining asubstantially enclosed, blow-shaped volume in the implantedconfiguration. The braided mesh can be movable from a substantiallytubular configuration having a first send and a second end to theimplanted configuration, and when in the implanted configuration, thefirst end and the second end can each be positioned approximate a centerof the bowl-shaped volume, and a fold in the braided mesh can define anannular ridge of the bowl-shaped volume.

An example method of occluding an aneurysm can include positioning anexpandable braid in a collapsed state within a microcatheter, distallysliding the braid through the microcatheter towards the aneurysm,expelling a first portion of the braid that includes a distal end of thebraid from the microcatheter into an aneurysm sac, expanding the firstportion of the braid, expelling a second portion of the braid includinga proximal end of the braid from the microcatheter into the aneurysmsac, expanding the second portion of the braid to occlude a neck of theaneurysm and to form an outer occlusive sack, and inverting the firstportion of the braid to form an inner occlusive sack nested within theouter occlusive sack. The second portion of the braid can be expanded toform the outer occlusive sack such that a proximal end of the braid ispositioned near a center of the neck of the aneurysm and the secondportion of the braid extends radially from the proximal end to form theouter occlusive sack. The braid can be self-expanding.

The method can include positioning a distal end of a second catheter fordelivering an embolic implant such that the distal end is positionedwithin the aneurysm sac. The step of expanding the second portion of thebraid can include confining the second catheter between the secondportion of the braid and a first portion of a wall of the aneurysm.

The method can include delivering the embolic implant to the aneurysmthrough the second catheter, implanting the embolic implant in theaneurysm sac, and providing a force from the embolic implant to apposeat least a portion of the braid to a second portion of the wall of theaneurysm.

The method can include providing a force between the outer occlusivesack and an aneurysm wall sufficient to maintain an implanted positionof the braid within the aneurysm.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and further aspects of this invention are further discussedwith reference to the following description in conjunction with theaccompanying drawings, in which like numerals indicate like structuralelements and features in various figures. The drawings are notnecessarily to scale, emphasis instead being placed upon illustratingprinciples of the invention. The figures depict one or moreimplementations of the inventive devices, by way of example only, not byway of limitation.

FIGS. 1A to 1B are illustrations of cross-sectioned exemplary implantsin a deployed state according to aspects of the present invention;

FIG. 1C is an illustration of an exemplary implant in a deployed stateas viewed from the distal end according to aspects of the presentinvention;

FIG. 2 is an illustration of an exemplary implant in a collapsed statein a microcatheter according to aspects of the present invention;

FIGS. 3A to 3F are illustrations of an implantation sequence of anexemplary implant according to aspects of the present invention;

FIGS. 4A to 4G are illustrations of another implantation sequence of anexemplary implant according to aspects of the present invention;

FIG. 5 is an illustration of an exemplary implant absent a distalclosure member implanted in a deployed state according to aspects of thepresent invention;

FIG. 6A is a perspective schematic view showing an exemplary deliverysystem for use with an example implant according aspects of the presentinvention;

FIG. 6B is a perspective schematic view of FIG. 6A but with partialcross-section of the delivery system and the implant according aspectsof the present invention;

FIG. 7A is a perspective schematic view of FIGS. 6A-6B being deployedwith partial cross-section of the delivery system and the implantaccording aspects of the present invention;

FIG. 7B is a perspective schematic view of FIGS. 6A-6B deployed with theexemplary delivery system detached from the implant according aspects ofthe present invention;

FIG. 8 is an illustration of another exemplary device having an implantin a collapsed state according to aspects of the present invention;

FIGS. 9A to 9C are illustrations of an exemplary implantation sequenceof the exemplary device of FIG. 8 according to aspects of the presentinvention;

FIG. 10 is a flow diagram outlining example method steps that can becarried out during implantation of an occluding implant according toaspects of the present invention.

DETAILED DESCRIPTION

In general, example devices described herein can include an implanthaving a flexible body expandable from a collapsed state in which theimplant is shaped to be delivered through a microcatheter to an aneurysmtreatment site to a deployed state in which the implant shaped toocclude an aneurysm from within an aneurysm sac. In the deployed state,the implant can generally have a bowl shape having an inner occlusivesack nested within an outer occlusive sack such that the outer occlusivesack and the inner occlusive sack are separated by a fold in theflexible body of the implant.

FIGS. 1A and 1B depict side views of a cross sectioned example implantsin a deployed state. As illustrated, an implant 100 can have a braidedmesh flexible body. The mesh can fold to define an inner occlusive sack104 and an outer occlusive sack 102 separated by a fold 103. The implant100 can have a distal end 114 and a proximal end 112, and each end 112,114 can be closed. A proximal end closure mechanism 122 can close theproximal end 112, and a distal closure mechanism 124 can close thedistal end 114. Closure mechanisms 122, 124 can be a crimped band or endcap such as is known in the art. Closure mechanisms 122, 124 can includea radiopaque material.

As illustrated in FIG. 1B, the proximal end closure mechanism 122 can beprotrude into the outer occlusive sack 102 of the bowl shape as can beadvantageous in some aneurysm treatments to avoid obstructing a bloodvessel adjacent to the aneurysm with the proximal end closure mechanism122.

FIG. 1C is an illustration of a view from a distal side of an exampleimplant 100 in a deployed state such as the implants depicted in FIGS.1A and 1B.

FIG. 2 is an illustration of an exemplary implant 100 in a collapsedstate in a microcatheter 600. In the collapsed state, the implant 100can have a substantially tubular shape having a proximal end 112, adistal end 114, and a braided or other flexible and expandable segment110 extending between the proximal end 112 and the distal end 114. Thebraided segment 110 can include flexible wires braided to form a tube ofwires that wrap helically around a center axis with roughly half of thewires wrapping clockwise, and the other half wrapping counterclockwisesuch that wires extending in opposite direction wrap over and under eachother diagonally in an alternating fashion. When the implant 100 is inthe collapsed state, the segment 110 can have sufficient flexibility tobe delivered through the microcatheter 600, navigating torturousanatomical geometries, to be delivered to a treatment site.

The implant 100 can include a proximal end closure mechanism 122, adistal end closure mechanism 124, or both a proximal and a distal endclosure mechanism 122, 124. The end closure mechanisms 122, 124 caninclude a radiopaque material, and can also serve as part of a means fordelivering the implant 100 through the microcatheter 600 to thetreatment site.

FIGS. 3A to 3F are illustrations of stages or steps that can occurduring an implantation sequence of an exemplary implant 100. Startingwith FIG. 3A, the implant 100 can be delivered to a treatment site bysliding the implant 100 distally in a collapsed state through amicrocatheter 600. FIG. 3A depicts a distal end 114 of the implant 100having a distal end closure mechanism 124 positioned within themicrocatheter 600 near a neck 16 of an aneurysm 10 for deployment intoan aneurysm sac 12. As illustrated in FIGS. 3A to 3F, the treatment sitecan include an aneurysm 10 positioned adjacent bifurcated blood vesselbranches 20 a, 20 b, and the implant 100 can be delivered to thetreatment site through a stem branch 21 feeding the bifurcated bloodvessel branches 20 a, 20 b.

FIG. 3B illustrates the distal end 114 including the distal closuremechanism 124 pushed out of the microcatheter 600. The expelled portionof the braided segment 110 can expand as it exits the microcatheter 600.The braided segment 110 can include a memory shape material such asNitinol, a Nitinol alloy, a polymer memory shape material, or othermemory shape material having properties for reshaping as describedherein. The braided segment 110 can be in a deformed shaped in thecollapsed state and reshape based on a predetermined shape after exitingthe microcatheter.

FIG. 3C illustrates further distal movement of the implant 100. As moreof the braided segment 110 exits the microcatheter 600, the braidedsegment 110 can continue to expand. The braided segment 110 can alsobegin to invert to begin to form a trough at the distal end 114.

FIG. 3D illustrates more of the braided segment 110 exiting themicrocatheter 600. As more of the braided segment 110 exits themicrocatheter 600, the braided segment 110 can continue to expand andinvert.

FIG. 3E illustrates the braided segment 110 almost entirely ejected fromthe microcatheter 600. As illustrated, the implant 100 can extend to aninterior wall 14 of the aneurysm 10.

FIG. 3F illustrates the implant in a deployed state in the aneurysm 10.In the deployed state, the braided segment 110 can fold to form an outerocclusive sack 102 and an inner occlusive sack 104 separated by a fold103. The outer occlusive sack 102 can extend radially from a proximalend 112 of the implant 100 to occlude at least a portion of the neck 16of the aneurysm 10. In the deployed state, the outer occlusive sack 102can deflect a blood flow from the aneurysm 10, diverting a blood flowfrom the aneurysm 10, slowing a blood from into the aneurysm 10, or anycombination thereof.

In the deployed state, the outer occlusive sack 102 can extend to theaneurysm wall 14, and the outer occlusive sack 102 can provide a forceagainst the aneurysm wall to maintain the implanted position of theimplant 100 such that the implant 100 doesn't become dislodged andbecome ineffective at inhibiting blood flow into the aneurysm. The forceof the outer occlusive sack 102 to the aneurysm wall 14 can besufficient to maintain the position of the implant 100 within theaneurysm 10. For example, the braided segment 110 can be made of amemory shape material having a first, predetermined shape and a second,deformed shape. The braided segment 110 can be in the deformed shapewhen the implant 100 is in a collapsed state. When the implant 100 is ina deployed state within the aneurysm 10, the braided segment 110 canmove to a third, deployed shape that is based at least in part on thefirst, predetermined shape and the anatomical geometry of the aneurysm10. In the example, the first, predetermined shape can be sized largerthan the wall 14 within the aneurysm sac 12; the braided segment 110 canmove to extend to the wall 14; and the braided segment 110 can provide aforce against the wall 14 as the properties of the memory shape materialcause the braid 110 to attempt to open to the predetermined shape.

The implant 100 can include a proximal end closure mechanism 122 such asan end cap, band, or other mechanism as known in the art positioned nearthe proximal end 112 of the implant, closing the braided segment 110.The end closure mechanism 122 can be placed centrally in relation to theaneurysm neck 16 opening. As such, the implant 100 can define asubstantially continuous occluding surface across the neck 16 of theaneurysm 10.

In the deployed state, the inner occlusive sack 104 can form a troughwithin the outer occlusive sack 102 such that the inner occlusive sack104 nests within the outer occlusive sack 102. The distal end 114 of theimplant 100 can be positioned centrally within the trough of the innerocclusive sack 104 and can be positioned centrally in relation to theopening of the aneurysm neck 16. For an implant 100 including both aproximal end closure mechanism 122 and a distal end closure mechanism124, when the implant 100 is in the deployed state and implanted in theaneurysm 10, the proximal end closure mechanism 122 and the distal endclosure mechanism 124 can be aligned along an axis positioned centrallywithin the aneurysm neck 16, the axis perpendicular to a plane of theaneurysm neck 16.

The inner occlusive sack 104 and the outer occlusive sack 102 cantogether form a substantially bowl-shaped structure or a substantiallyenclosed bowl-shaped volume. The inner occlusive sack 104 and outerocclusive sack 102 can be separated by a fold 103. The fold 103 candefine an annular ridge of the bowl-shaped structure or volume. The fold103 can be positioned to appose an annular surface of the aneurysm wall14. The bowl-shaped structure defined by the braided mesh 110 can have asubstantially contiguous surface extending radially from the proximalend 112 outwardly across the aneurysm neck 16 and upwardly apposed tothe aneurysm wall 14, then folding down and radially inward forming atrough that converges at the distal end 114 of the braided mesh 110. Afirst portion of the braided segment 110 can be capable ofself-expanding to form the outer occlusive sack 102 and a second portionof the braided segment 110 can be capable of self-inverting to form theinner occlusive sack 104.

FIGS. 4A to 4G are illustrations of stages or steps that can occurduring another example implantation sequence of an exemplary implant.FIG. 4A illustrates an embolic implant delivery catheter 200 having adistal end positioned within an aneurysm sac 12. FIG. 4B illustrates amicrocatheter 600 positioned at a neck 16 of the aneurysm 10 having animplant 100 positioned within the microcatheter 600 near the aneurysmneck 16. Both the embolic implant delivery catheter 200 and themicrocatheter 600 delivering the implant 100 can be delivered to thetreatment site through a stem blood vessel 21 when treating an aneurysmat a bifurcation.

FIG. 4C illustrates the expansion of the braided segment 110 as thebraided segment exits the microcatheter 600 like as illustrated in FIG.3B. Referring to FIG. 4C, the expanding segment can begin to pushagainst the embolic implant delivery catheter 200.

FIG. 4D illustrates the implant 100 in a deployed state within theaneurysm sac 12. The deployed implant can provide a force against theembolic implant delivery catheter 200, pushing the embolic implantdelivery catheter 200 against the aneurysm wall 14. In thisconfiguration, the embolic implant delivery catheter 200 can be “jailed”such that the force provided by the implant apposes the embolic implantdelivery catheter 200 to the aneurysm wall 14 and holds the emboliccatheter in place, inhibiting movement of the embolic implant deliverycatheter 200 within the aneurysm sac 12.

FIG. 4E illustrates an embolic implant 300 such as an embolic coil beingimplanted into the aneurysm sac 12 via the embolic implant deliverycatheter 200. The occlusive implant 100 in the deployed state within theaneurysm 10 can inhibit the embolic implant 300 from exiting through theneck 16 of the aneurysm 10. The embolic implant 300 can fill abowl-shaped occlusive implant, providing a force from within the troughof the bowl pushing the occlusive implant outwardly against the aneurysmwall 14. The force from the embolic implant 300 can serve to maintain animplanted position of the occlusive implant 100 and the embolic implant300 once treatment is completed.

FIG. 4F illustrates the embolic implant delivery catheter 200 beingdistally withdrawn following the completion of implanting the embolicimplant 300.

FIG. 4G illustrates the aneurysm following extraction of themicrocatheter 600 and the embolic implant delivery catheter 200,completing the implantation process.

FIG. 5 is an illustration of an exemplary implant absent a distalclosure member implanted in a deployed state.

FIGS. 6A to 7B generally illustrate example attachment and deliverybetween delivery tube 400 and braid 110 for deploying and detachingbraid 10 in aneurysm 10. The examples of FIGS. 6A to 7B depict one waythat delivery tube 400 and braid 110 may be attached, however, as willbe understood, any number of attachment means known in the art arecontemplated as needed or required.

FIGS. 6A and 6B illustrate an implant having a locking member 454affixed to the proximal end 112 of the braid 110 engaged with a deliverysystem at a distal end of the delivery tube 400. The delivery systemshown includes a loop wire 458 extending through a lumen of the deliverytube 400 bent at a distal end to travel through an opening 459 of thelocking member 454 and a locking rod 452 extending through the lumen ofthe delivery tube adjacent to the loop wire 458 and extending through adistal opening 460 of the loop wire 458. As illustrated in FIG. 6B, whenthe locking rod 452 is put through the distal opening 460 of the loopwire 458 and the loop wire 458 is fed through the opening 459 of thelocking member 454, the braid 110 can be engaged with the distal end 414of the delivery tube 400.

The delivery tube 400 can include a compressible portion 438 that canallow the delivery tube 400 to bend and/or flex. Such flexibility canassist tracking the implant 100 through a microcatheter and tortuouspaths of a vasculature. The compressible portion 438 can also bedelivered in a longitudinally compressed state that can extend to ejectthe braid 110 during deployment of the braid 110 as explained inrelation to FIGS. 7A and 7B.

FIG. 7A illustrates the locking rod 452 being pulled proximally, exitingthe distal opening 460 of the loop wire 458, and pulling free of theloop wire 458. Once the locking rod 452 has exited the distal opening460 of the loop wire 458, at least a portion of the loop wire 458 nearthe distal opening 460 can reshape to exit the opening 459 of thelocking portion 454.

As illustrated in FIG. 7B, once the loop wire exits the opening 459 ofthe locking portion 454, the braid 110 can disengage the delivery tube400. The compressible portion 38 of the delivery tube 30 can expandedand spring forward, imparting a distally directed force E from thedistal end 414 of the delivery tube 400 to the braid 110 to push thebraid 110 away from the delivery tube 400 to insure a clean separationand delivery of the implant 100.

FIG. 8 illustrates another exemplary implant 100 a being delivered byanother delivery system. The delivery system can include a pusher tube510 for engaging a distal end cap or band 124 a of the implant 100 a anda pusher bump 520 for engaging a proximal end 112 a of the implant 100a. The implant 100 a can have a substantially tubular shape sized sothat a majority of the implant 100 a is sized to fit within the pushertube 510 and a distal end member 124 a is sized larger than an innerdimension of the pusher tube 510. As illustrated in FIG. 8, distaltranslation of the pusher tube 510 can push the distal end member 124 adistally, moving the implant 100 a through the microcatheter 600 to atreatment site.

FIGS. 9A to 9C are illustrations of stages or steps that can occurduring another example implantation sequence of an exemplary implantsuch as the implant 100 a illustrated in FIG. 8. FIG. 9A illustrates amicrocatheter 600 positioned at a neck 16 of the aneurysm 10 having animplant 100 a positioned within the microcatheter 600 near the aneurysmneck 16. The implant 100 a can be delivered to the treatment sitethrough a stem blood vessel 21 when treating an aneurysm at abifurcation, and the pusher tube 510 can be used to translate theimplant 100 a through the microcatheter 600.

FIG. 9B illustrates the implant 100 a ejected from the microcatheter 600and in the process of moving to a deployed state. The implant 100 a canbe pushed out of the pusher tube 510 and the microcatheter 600 bypushing a pusher bump 520 distally. The pusher bump 520 can be attachedto a core wire or other elongated member and can be manufactured bymeans known in the art.

FIG. 9C illustrates the implant 100 a in the deployed state similar toas described and illustrated in relation to examples herein.

FIG. 10 is a flow diagram outlining example method steps that can becarried out during implantation of an occluding implant. The methodsteps can be implemented by any of the example means described herein orby any means that would be known to one of ordinary skill in the art.

Referring to a method 700 outlined in FIG. 10, in step 710 an expandablebraid can be positioned within a microcatheter such that the expandablebraid is in a collapsed state within the microcatheter. In step 720, thebraid can be slid distally through the microcatheter towards ananeurysm. In step 730, a first portion of the braid that includes adistal end of the braid can be expelled from the microcatheter into asac of the aneurysm. In step 740, the first portion of the braid can beexpanded. In step 750, a second portion of the braid including aproximal end of the braid can be expelled from the microcatheter intothe sac of the aneurysm. In step 760, the second portion of the braidcan be expanded to occlude a neck of the aneurysm and to form an outerocclusive sack such that the proximal end of the braid is positionednear the center of the aneurysm neck and the second portion of the braidextends radially from the proximal end to form the outer occlusive sack.In step 770, the first portion of the braid can be inverted to form aninner occlusive sack nested within the outer occlusive sack. In step780, the outer occlusive sack can provide a force against the aneurysmwall that is sufficient to maintain an implanted position of theexpanded braid within the aneurysm.

The descriptions contained herein are examples of embodiments of theinvention and are not intended in any way to limit the scope of theinvention. As described herein, the invention contemplates manyvariations and modifications of the device for occluding an aneurysm,including alternative geometries of elements and components describedherein, utilizing any number of known means for braiding, knitting,weaving, or otherwise forming the expandable section as is known in theart, utilizing any of numerous materials for each component or element(e.g. radiopaque materials, memory shape materials, etc.), utilizingadditional components including components to deliver an implant to atreatment site or eject an implant from a delivery catheter, orutilizing additional components to perform functions not describedherein, for example. These modifications would be apparent to thosehaving ordinary skill in the art to which this invention relates and areintended to be within the scope of the claims which follow.

What is claimed is:
 1. A device for occluding an aneurysm comprising: animplant movable from a collapsed state to a deployed state, the implantcomprising a proximal end, a distal end, and a braided segment forming asubstantially continuous braided structure between the proximal end andthe distal end, wherein in the deployed state, the implant comprises: anouter occlusive sack extending from the proximal end of the implant andcapable of occluding an aneurysm neck; an inner occlusive sack extendingform the distal end of the implant and forming a trough within the outerocclusive sack; and a fold in the braided segment positioned between theouter occlusive sack and the inner occlusive sack.
 2. The device ofclaim 1 wherein a first portion of the braided segment is capable ofself-expanding to form the outer occlusive sack and a second portion ofthe braided segment is capable of self-inverting to form the innerocclusive sack.
 3. The device of claim 1 wherein in the deployed state,the outer occlusive sack is capable of extending to an aneurysm wall toprovide a force against the aneurysm wall.
 4. The device of claim 1wherein in the deployed state, opposition of the outer occlusive sack toan aneurysm wall is sufficient to maintain the position of the implantwithin the aneurysm.
 5. The device of claim 1 further comprising anembolic filler, wherein the embolic filler is implantable in a sac ofthe aneurysm, wherein in the deployed state, the implant inhibits theembolic filler from exiting the sac, and wherein the embolic fillerprovides a force apposing the implant to an aneurysm wall.
 6. The deviceof claim 1 wherein in the collapsed state, the implant is sized to bedelivered to the aneurysm through a microcatheter.
 7. The device ofclaim 1 wherein one or more of the proximal end of the implant or thedistal end of the implant is closed.
 8. The device of claim 7 whereinone or more of the distal end or the proximal end is closed by one of aband, an end cap, or heat set.
 9. The device of claim 1, wherein thebraided segment comprises a memory shape material, the braided segmentcomprising a first, predetermined shape and a second, deformed shape,wherein the braided segment is in the second, deformed shape when theimplant is in the collapsed state, and wherein the braided segment movesto a third, deployed shape when the implant is in the deployed state,the third, deployed shape based at least in part on the predeterminedshape and a curvature of an aneurysm wall.
 10. The device of claim 1wherein in the deployed state, the outer occlusive sack is capable ofsealing the aneurysm neck to at least one of deflect, divert, and slow aflow into the aneurysm.
 11. The device of claim 1 wherein in thedeployed state, the implant defines a substantially enclosed volume. 12.The device of claim 1 wherein in the deployed state, the distal end andproximal end of the implant are each positioned along an axisapproximately perpendicular to a plane defined by the aneurysm neck andapproximate a center of the aneurysm neck.
 13. The device of claim 1wherein the implant is implantable in an aneurysm adjacent bifurcatedblood vessel branches, and wherein the implant is deliverable to theaneurysm through a stem branch feeding the bifurcated blood vesselbranches.
 14. An implant for treating an aneurysm comprising a braidedmesh, wherein the braided mesh is movable to an implanted configuration,the braided mesh comprising a substantially contiguous surface defininga substantially enclosed, bowl-shaped volume in the implantedconfiguration.
 15. The implant of claim 14 wherein the braided mesh ismovable from a substantially tubular configuration having a first endand a second end to the implanted configuration, and wherein, in theimplanted configuration, the first end and the second end are eachpositioned approximate a center of the bowl-shaped volume and a fold inthe braided mesh defines an annular ridge of the bowl-shaped volume. 16.A method of occluding an aneurysm, comprising: positioning an expandablebraid within a microcatheter, the braid being in a collapsed statewithin the microcatheter and comprising a distal end and a proximal end;distally sliding the braid through the microcatheter towards theaneurysm; expelling a first portion of the braid including the distalend of the braid from the microcatheter into a sac of the aneurysm;expanding the first portion of the braid; expelling a second portion ofthe braid including the proximal end of the braid from the microcatheterinto the sac of the aneurysm; expanding the second portion of the braidto occlude a neck of the aneurysm and to form an outer occlusive sack,wherein the proximal end of the braid is positioned approximate a centerof the neck of the aneurysm and the second portion of the braid extendsradially from the proximal end to form the outer occlusive sack; andinverting the first portion of the braid to form an inner occlusive sacknested within the outer occlusive sack.
 17. The method of claim 16further comprising: positioning a distal end of a second catheter fordelivering an embolic implant such that the distal end is positionedwithin the aneurysm sac, and wherein the step of expanding the secondportion of the braid further comprises confining the second catheterbetween the second portion of the braid and a first portion of a wall ofthe aneurysm.
 18. The method of claim 17 further comprising: deliveringthe embolic implant to the aneurysm through the second catheter;implanting the embolic implant in the aneurysm sac; and providing aforce from the embolic implant to appose at least a portion of the braidto a second portion of the wall of the aneurysm.
 19. The method of claim16 wherein the braid is self-expanding.
 20. The method of claim 16further comprising providing a force between the outer occlusive sackand an aneurysm wall sufficient to maintain an implanted position of thebraid within the aneurysm.